In the reproduction or fabrication of complex surfaces, it is often essential to determine the spatial locations of points on the surface. In order to reproduce or fabricate a surface with substantial precision, it is necessary to specify a substantially large number of closely-spaced points.
Heretofore, the measurement of points on a complex surface was carried out in a laborious manner by recording the positions of the points methodically until the surface has been specified with the required amount of precision. The taking of measurements of the points on the surface often involved making contact with the surface with an instrument, for example. The final amount of recorded data, furthermore, was voluminous and difficult to analyze. In view of the large amount of data which had to be recorded with respect to a large number of points in order to achieve a predetermined precision, it was particularly susceptible to the introduction of measuring and recording errors.
Accordingly it is an object of the present invention to provide an arrangement in which a surface is scanned and subdivided into a substantially large number of sections, so that points on the surface may have their positions sensed or found and determined with substantially high resolution.
Another object of the present invention is to provide an arrangement in which each of the subdivided sections of the surface is assigned a predetermined code which defines the section uniquely from the other sections.
A further object of the present invention is to provide an arrangement of the foregoing character in which the surface may be scanned a minimum number of times to achieve a predetermined resolution of sections and accompanying precision.
A still further object of the present invention is to provide an arrangement, as described, in which the spatial positions of points within each section may be determined by correlating the points to a reference surface scanned independently by the projector and photographed by a camera.
It is a particular object of the present invention to sense the characteristics of the surface and determine the positions of points thereon without physically contacting the surface, by carrying out the procedures involved with optical means.